Circulating device for hot-water heating systems.



A. E. CROWHURST.

CIRCULATING DEVICE FOR HOT WATER HEATING SYSTEMS.

APPLICATION FILED OCT. 23.1917.

Patented Jan. 7, 1919.

W T N w M Q ALBERT E. CROWHURST, OF HUMBER BAY, ONTARIO, CANADA.

CIRCULATING DEVICE FOR HOT-WATER HEATING SYSTEMS.

To all whom it may concern:

Be it lmown that I, ALBERT E. CROW- HUBST, of Humber Bay, in the county of York, Province of Ontario, Canada, have invented certain new and useful Improvements in Circulating Devices for Hot-Water Heating Systems, of which the following is a specification. V V

This invention relates to devices for accel crating, when desired, the circulation of the water in a gravity hot water heating system. Any such device, when not in operation, must in no Way interfere with a free gravity circulation, and my object is to devise a simple construction whereby the impeller of the circulating device will automatically adjust itself to an operative or inoperative position according as it is driven or left idle.

I attain my object by using as an impeller in the circulating device a fan with radially journaled blades, the blades having their centers of effort forward of the axes on which the blades are journaled, whereby the water resistance, when the fan is rotated, tends to turn the blades to their operative ,positions and the water flow, assisted by springs, tends to turn the blades to their inoperative positions when the fan is not rotated, by locatin the axes on which the blades are journa ed behind the blades and by extending said blades substantially to the center of the impeller.

The whole is constructed in detail substantially as hereinafter described and illustrated in the accompanying drawings in which- Figure 1 is a longitudinal section of part of the circulating system of the hot water heating system provided with my improved circulating device;

Fig. 2 a front elevation of the fan showing the blades in the position they assume when the fan is inoperative;

Fig. 3 a plan view of the fan showing the blades in the position they assume when the fan is inoperative;

- Fig. 4 a plan view of the fan showing the blades in the position they assume when the fan is operative; and

Fig. 5 a sectional detail showin one of the springs tending to turn one o the fan blades to its inoperative position.

In the drawings like numerals of reference indicate corresponding parts in the different figures.

Specification of Letters Patent.

1 1s a cylindrical casing, preferably con- Patented Jan. 7, 1919.

Application filed October 23, 1917. Serial No. 198,081.

nected with or forming part of a header with which the return flow risers of the circulating system are connected. 2 is a shaft extending into the interior of the casing and journaled at .its inner end in the bearing 3 supported from the cap 10 closing, an opening in the casing through which the device is inserted. The other end of the shaft is supported in the external bearing 4, the opening through which the shaft passes being provided with a stufling box 5.

A hub 13 at the inner end. of the shaft has a plurality of radial journals 6 formed on or secured thereto. On these journals the bearing sleeves 7 are rotatable, and are held in place 'by the screws 11 threaded into the ends of the journals. These bearing sleeves are connected to the rear. sides of the fan blades 8, which, with the shaft, form an impeller adapted to effect a forced circulation of water through the cylindricalcasing.

Owing to the bearings of the fan blades being located behind the blades, it is possible to extend the inner ends of the fan blades very close to the center of the shaft 2. It will be noted that the fan blades 8 are so shaped that their'centers of efiort are lo' cated forward of the axes on which said blades are journaled. The result of this construction is that when the shaft is rotated the resistance of the water causes the blades to rock to the inclined working position illustrated in Fig. 4. The rocking movement of the blades is limited and the working'position fixed by any suitable means. I show a shoulder on each bearing sleeve adapted to engage a shoulder 12 on the hub 13. The effect produced by the unbalanced form of the blades is also enhanced by the journal'- ing of the blades with their axes in rotation behind'the blades as previously described.

When the shaft is not being driven and the heating system is-inoperative, there is a flow of water through the system due to gravity. This flow will producea pressure on the fan blades 8 which will tend to cause them to assume the position with their ends edgewise to the direction of the flow as shown infull lines in Fig. 2. I prefer, however, to employ for each blade a coil spring 14 located in a recess formed between the bearing sleeve 7 and the journal 6 and havin its ends connected respectively to the said journal and sleeve. These springs while strong enough to turn the blades when the fan is stationary are not strong enough to prevent the blades turning when the fan is rotated.

I have found that in constructions in which the propulsive effect of the impeller is largely produced at some distance from the center of the shaft there is a tendency to produce a circulation of water the casing itself rather than through the whole of the circulating system of the heating system. As my present construction permits of the fan blades extending nearly to the center of the shaft, such local or eddy circulation is entirely prevented, the blades having an effective propelling effect almost to the center of the column of water in the casing.

For driving purposes I secure to the outer end of the shaft a pulley 9 preferably grooved. It will be found that the construction above described will satisfactorily attain the objects of my invention as set out in the preamble to this specification.

What I claim as my invention is:

1. In a gravity hot water heating system, the combination with the circulating system of a cylindrical casing included therein; and an impeller comprising a suitably journaled shaft extending into said casing from the exterior thereof; flat fan blades journaled radially on said shaft within the casing on axes behind the blades, the fan blades also having their centers of effort forward of the axes on which said blades are journaled, and stops determining the normal working position of the blades, said blades being free to turn to a position parallel to the axis of the shaft.

2. In a gravity hot water heating system, the combination with the circulating system of a cylindrical casing included therein; and an impeller comprising a suitably journaled shaft extending into said casing from the exterior thereof; flat fan blades journaled radially on said shaft within the easing on. axes behind the blades, the blades extending inwardly in front of the bearings substantially to the center of the impeller, the fan blades also having their centers of effort forward of the axes on which said blades are journaled, and stops determining the normal working position of the blades, said blades being free to turn to a position parallel to the axes of the shaft.

3. In a gravity hot water heating system, the combination with the circulating system of a cylindrical casing included therein; an

impeller comprising a suitably journaled shaft extendin into said casing from the exterior thereo flat fan blades journaled radially on said shaft within the casing on axes behind the blades, the fan blades having their centers of effort forward of the axes on which said blades are journaled; stops determining the normal working position of the blades, said blades being free to turn to a position parallel to the axis of the shaft; and coil springs tending to rotate the fan blades to a position parallel to the direc-' tion of flow in the casing.

Signed at Toronto, Can.,'this 27th day of September, A. D. 1917.

ALBERT E. onownunsr. 

